Fluorinated acids and esters

ABSTRACT

PERFLUOROALKYL-TERMINATED ALKYL MALONIC ACIDS AND ESTERS OF THE FORMULA (R1-R&#39;&#39;)ACH2-A(COOR)2 PREPARED FROM THE CORRESPONDING MALONIC ACID ESTER AND R1-R&#39;&#39;-Z. THE ESTERS ARE USEFUL TO PREPARE PERFLUOROALKYL-TERMINATED ALKYL-1,3-PROPANEDIOLS OF THE FORMULA   (R1-R&#39;&#39;)ACH2-A(CH2OH)2   BY REDUCTION. THE ESTERS AND DIOLS CAN BE USED TO PREPARE POLYESTERS AND POLYURETHANES WHICH ARE IN GENERAL USEFUL AS FABRIC COATINGS TO IMPART OIL- AND WATER-REPELLENCY THERETO.

United States Patent 3,578,701 FLUORINATED ACIDS AND ESTERS Kenneth C. Smeltz, Graylyn Crest, Wilmington, Del., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del.

No Drawing. Original application July 26, 1967, Ser. No. 656,076, now Patent No. 3,478,116, dated Nov. 11, 1969. Divided and this application Feb. 28, 1969, Ser. No. 803,469

Int. Cl. C07c 55/08, 69/62 U.S. Cl. 260-485 11 Claims ABSTRACT OF THE DISCLOSURE Perfiuoroalkyl-terminated alkyl malonic acids and esters of the formula (R -R'-),,CH J,,(COOR) prepared from the corresponding malonic acid ester and R,RZ. The esters are useful to prepare perfiuoroalkyl-terminated alkyl-1,3-propanediols of the formula by reduction. The esters and diols can be used to prepare polyesters and polyurethanes which are in general useful as fabric coatings to impart oiland water-repellency thereto.

CROSS-REFERENCE TO RELATED APPLICATION This application is a division of application Ser. No. 656,076, filed July 26, 1967, now U.S. Pat. No. 3,478,116.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates to perfiuoroalkyl-terminated alkyl derivatives of malonic acid and its esters.

(2) Description of the prior art SUMMARY OF THE INVENTION This invention is directed to perfluoroalkyl-terminated alkyl malonic acids and esters thereof represented by the structural formula wherein R, is perfluoroalkyl of 4-20 carbons, R is alkylene of 2-12 carbons, R is hydrogen or lower alkyl, and a is the whole number 1 or 2. The compounds of Formula 1 are prepared by reacting R,R-Z with CH (COOR) wherein R" is lower alkyl and Z is a displaceable group, in the presence of a carbanionic-producing reagent. A spanonification reagent is then employed to obtain the compounds wherein R is hydrogen.

DESCRIPTION OF THE INVENTION (A) The malonic acid and ester derivatives of this invention As is seen from Formula 1, these derivatives are monosubstituted (a.=1) or disubstituted (:2) derivatives of malonic acid. The perfluoroalkyl group R, can be either straight chain or branched chain, and is defined herein as including cyclic perfluoroalkyl although these latter groups are less desirable because of their general unavailability. Preferably, R contains 6-12 carbon atoms and is straight chained. Representative perfluoroalkyl groups include the perfluorinated groups derived from butyl, amyl, hexyl, heptyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, isoamyl, isoheptyl, cyclobutyl, cyclohexyl, methylcyclohexyl and the like. Of these, the groups hexyl to dodecyl are preferred.

The group R is preferably the divalent straight-chain group (CI-1 where m is 2-12, although it can be branched. Most preferably, m is a cardinal number of 24. Representative R groups include ethylene, butylene, decylene and dodecylene. The R is represented by hydrogen, methyl, ethyl, propyl, butyl, tert.-butyl, hexyl and the like. The term lower as used herein is defined as a chain containing 1-6 carbon atoms.

The compounds of Formula 1 are prepared by reacting the starting material CH (COOR") where R" is lower alkyl with R RZ in the presence of a reagent capable of converting CH (COOR) to the anion Z is a displaceable group and is preferably a carbonate, nitrate, halogen, (chlorine, bromine or iodine) or arylene sulfonates, such as the toluene-sulfonate ester. The halogens and arylene sulfonates are preferred. A number of bases capable of forming the carbanion [CH(COOR") are known. These include alkali metal alkoxides, such as sodium butoxide, potassium methoxide, and rubidium isopropoxide; alkali metal amides, sodium triphenylmethide, sodium hydride or sodium or potassium metal.

The reaction procedure is described generally by Cope, Holmes and House in chaper 4, volume 9, of Organic Reactions, Wiley, 1957. Reaction pressure, amounts of ingredients and time of reaction are generally not critical. The reaction is preferably carried out employing an alkali metal alkoxide as the base, in which case the alcohol precursor of the alkoxide is used in excess as the solvent. Reaction temperatures are preferably reflux temperatures, and the reaction is carried out under substantially anhydrous conditions. When only one (R -R) group is desired in the final product, any of the above-listed bases can be employed; but when two (R -R) groups are desired, the stronger alkoxide bases such as sodium or potassium tert.-butoxide are preferred.

The initial products obtained by the reaction are the esters wherein R of Formula 1 is lower alkyl. The corresponding acids (wherein R of Formula 1 is hydrogen) are obtained by saponification of the ester.

The reactants employed in the process are readily available and are well known in the art, except for the R R- arylsulfonate esters which are prepared from the wellknown alcohols R,-R'OH by reaction with arylsulfonyl chlorides using the Schotten-Bauman technique in the presence of a base such as sodium hydroxide.

The malonic acid derivatives of Formula 1 are useful for preparing condensation polymers with the 1,3-propanediols described below. The acids can also be monodecar boxylated by well-known procedures to result in compounds of the formula (R R'),CH ,,COOH which are useful as described in U.S. 2,951,051.

(B) 1,3-propanediols Compounds of the formula t 7ia 2a( Z )2 are obtained by reducing a compound of Formula 1 to the corresponding diol of the above Formula 2. Hence, the

discussion concerning the nature of R R and a in Section A immediately above is applicable to these propanediols.

The reduction of carboxyl or ester groups to primary alcohol groups is Well known. Ester-containing compounds (those of Formula 1 wherein R is lower alkyl) are preferred as the starting material. Reduction reagents include hydrogen and catalysts, alkali metal aluminum hydrides or borohydrides, and the like. More specifically, when the compounds of Formula 1 where R is lower alkyl (the esters) are employed, strong reducing conditions are preferred. Thus, such reducing agents as hydrogen and rhodium or ruthenium, or sodium and absolute alcohol, and the like, are preferred.

The reaction conditions will vary widely depending upon the reducing reagents used. These conditions are well known in the art, as for example, Organic Reactions, W01. 6, chapter 10, Wiley, 1951; Wagner and Zook, Synthetic Organic Chemistry, Section 84, pp. 155-157, Wiley, 1953; and Gilman, Organic Chemistry, 2nd ed., vol. 1, pp. 827-831, Wiley, 1949.

The 1,3-propanediols described in this Section B are useful in preparing condensation polymers. For example, by reaction with dibasic organic acids, polyesters are obtained; and by reaction with diisocyanates, polyurethanes are obtained. These procedures are described below.

(C) THE POLYMERS (1) Polyesters derived from F iE LJ Z 2 and dibasic acids: These polyesters are derived from the diols of Formula 2 and organic dibasic acids of the formula A(COOH) wherein A is an aromatic group of 6-16 carbon atoms or a saturated aliphatic group of -16 carbon atoms. The polymers may be formed just from the diol of Formula 2 and the acid A(COOH) or they may be formed from said diol and acid and nonhalogenated group of 2-28 carbons, and is preferably divalent alkylene of 2-12 carbons. The molar ratio of the diol of Formula 2 to the diol D(OH) is at least 0.25 to 1.

Perferably A is divalent alkylene, divalent arylene, oxygen-interrupted divalent alkylene or oxygen-interrupted divalent arylene. Most preferably, A is divalent alkylene of 0-16 carbon atoms or arylene of 6-16 carbon atoms. Representative examples of diacids useful herein include oxalic, malonic, succinic, glutaric, adipic, pimelic, superic, azelaic, sebacic, brassylic, thapsic, octadecanedioic, ether diacids such as diglycolic acid, diacids containing alicyclic rings such as 1,4-cyclohexanedicarboxylic acid and 4,4'-dicyclohexyl-l,1-dicarboxylic acid, and aromatic diacids such as phthalic acid, isophthalic acid, terephthalic acid, methylphthalic acid, chlorophthalic acid, diphenyl-2,2'-dicarboxylic acid, diphenyl-4,.4'-dicarlboxylic acid, 1,4-naphthalene dicarboxylic acid, 1,8-naphthalene dicarboxylic acid, diphenylmethane2,2'-dicarboxylic acid, diphenylmethane-33'-dicarboxylic acid and diphenlymethane-4,4'-dicarboxylic acid, and the like.

Representative diols D(OH) useful herein include ethylene glycol, 1,2-propylene glycol, 1,2-butylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, 2-ethyl-1,3-butylene glycol, octamethylene glycol, 2-ethyl-1,3-hexanediol, decamethylene glycol, dodecamethylene glycol, tetradecamethylene glycol, hexadecamethylene glycol and octadecamethylene glycol, and diols containing ether groups such as diethylene glycol, triethylene glycol, tetraethylene glycol, octaethylene glycol, decaethylene glycol, and the corresponding polytetramethylene glycols of structure H150 (CH2)4 0H where n is from two to seven or more. The diol D(OH) may also contain alicyclic rings, such as 1,4-cyclohexanediol, 1,4-bis(hydroxymethyl)cyclohexane, 4,4'-dihydroxy-1,1-dicyclohexyl and the like. The lower glycols such as ethylene glycol, propylene glycol and the like are preferred.

The molar amount of diol or diols and acid in the 4 polymeric product will be approximately equal. When just [R R'-],CH (CH OH) and A(CO H) are condensed together, the polymers contain the repeating unit:

When mixtures of diols are used, random arrangement probably occurs. One possible grouping is:

f' t it i H TOCHQCUR'RQB(H)2-r-CH2OCAC-OD-O-CA e In every case, it is readily seen that one mole of diacid A(CO H) is required for each mole of diol or diols and vice-versa. By using an excess of diol or diacid, one can tend to control whether the polymer chains are terminated by carboxyl or hydroxyl groups.

These polyester condensation polymers are prepared by techniques well known for the manufacture of polyesters. Ordinarily, mixtures of the diols and esters of the diacids are heated together in the presence of an acidic transesterification catalyst such as antimony trioxide, tetraisopropyl titanate, toluenesulfonic acid, and the like. Volatile alcohol esters such as methyl or ethyl are generally preferred, Le. or A(CO2C2H5)2, and the heating iS carried out at temperatures sufiicient to cause the volatile alcohol of such ester to distill. In most instances, temperatures in the range of C. to 320 C. are suflicient. Usually, a reduced pressure is applied to the reaction vessel in the latter stages of the reaction, along with higher temperatures, to keep the mass fluid and to remove last traces of volatile alcohol. When no further polymerization occurs, generally as judged by no further increase in viscosity of the reaction mass, the polymer is collected and cooled.

When a mixture of [R;R'],,CH ,,(CH OH) and D(OH) is being used to polymerize with A(CO H) special considerations apply to the relative amounts of the two diols used. An excess of the more volatile diol (often but not necessarily D(OH)2) may be added. The mole ratio of two diols in the final product is controlled by the mole ratio of less volatile diol to diacid in the original mixture. For example, if the original reaction mixture contains one mole R;RCH(CH OH) two moles A(CO CH and three moles ethylene glycol, then when reaction with the diester is initially complete, theoretically the two species A(CO CH CI-I OH) and could exist in the mixture. The two further equilibrium reactions a and b below could occur on further heating.

Since ethylene glycol is more volatile than the glycol R RCH(CH O'H) reaction (a) is driven to the right by distillation of ethylene glycol in preference to driving reaction (b) to the right. Further condensation of the product of reaction (a) with loss of ethylene glycol eventually leads to a product containing essentially equimolar amounts of the two glycols. Similarly, if the initial mixture were in the molar ratio 3 R R'CH (CH OH) 3HOCH CH OH/ 4A(CO CH 2 the final polymer would be in the ratio 3R,RCH(CH OH) HOCH CH OH/4A(CO H) Or, if the initial ratio were R;R'CH CH OH) GHOCH CH OH/ 4A (CO CH the final ratio would be R -R' CH (CH OH 3HOCH CH OH/4A(CO H) 2 (2) Polyesters derived from (R RQ CH JCOOHh and diols: These polymers are derived from the acid form of the monomers of Formula 1 and diols of the formula E(OH) wherein E is defined the same as D in Section Cl above, or is a halogenated diol of the formula HO CH (CF CH OI-I wherein n is a cardinal number of from 2 through 8.

Representative diols D(OH) have been listed above and representative halogenated diols are described in McBee et al., J. Amer. Chem. Soc., 74, 444 (1952).

These polyester will contain the repeating unit broadly and, more narrowly, the units o (RRt)a(H)2a -O onto (0 F2)nCH2OJ These polyesters are prepared by heating approximately equimolar quantities of a lower alkyl enter (methyl, ethyl, propyl, butyl) of the acid [R --R'] CH ,,,(CO H) and the diol E(OH) in the presence of the same type of acid catalyst and conditions as described in Section C-l. When the diol E(OH) is a mixture of two diols (or more), the comments in Section C-l above concerning relative volatility of the individual diols and molar ratios in the product polymer applies here also.

(3) Polyurethanes derived from and diisocyanates: These polymers are prepared from the monomers of Formula 2 and diisocyanates of the Formula B(NCO) wherein B is a saturated aliphatic group of 2-16 carbons or an aromatic group of 6-16 carbons; and may also contain units derived from the D(OH) described previously. When such a mixture of diols is used, the molar ratio of the diols of Formula 2 to the diols D(OH) is at least 0.25 to 1 and is preferably at least 1 to l.

The diisocyanates must be free of substituents which react with isocyanate groups. Preferably the diisocyanates are unsubstituted. Thus B is preferably divalent alkylene or divalent arylene. Representative diisocyanates useful herein include aliphatic isocyanates of structure OCN (CH NCO such as l,2-ethane diisocyanate, 1,3-propane diisocyanate, 1,4-butane diisocyanate, 1,6-hexane diisocyanate, 1,8-octane diisocyanate, 1,10-decane diisocyanate, 1,12-dodecane diisocyanate, 1,16-hexadecane diisocyanate, and other aliphatic diisocyanates such as 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate. Useful examples of aromatic diisocyanates include 2,4-toluene diisocyanate,

2,6-toluene diisocyanate, 1-nitrophenyl-3,S-diisocyanate, 4,4'-diisocyanatodiphenyl ether, 3,3-dichloro4,4-diisocyanatodiphenyl ether, 4,4-diisocyanatodiphenyl methane,

These polymers contain the repeating unit 0 T0 H2 (R' r)a(H)2aCHzO NHBNHp) -I when only [R;R'-] CH ,,(CH OH) and B(N-CO) are used. When mixtures of the fluorinated diol and nonhalogenated diol D-(OH) are used, random arrangement probably occurs but one possible grouping is It is readily seen that approximately one mole of diisocyanate B(NCO) is required for each mole of diol used.

These polyurethanes are prepared by mixing together approximately equimolar amounts of the diisocyanate and diols, generally with agitation. If a mixture of diols is being used, it is generally preferable to mix the diols thoroughly before combining with the diisocyanate if a random arrangement is desired. If a non-random arrangement is desired, one diol may be added to the isocyanate and, when reaction is near completion, the second diol is added. The reaction mass usually becomes somewhat viscous as reaction proceeds. Heating, say at 40 C. or higher, may be necessary to maintain the mass in a sufficiently fluid condition to allow agitation.

Alternatively, an inert solvent or diluent may be added to maintain fluidity. Such solvents would include aromatic hydrocarbons such as benzene, toluene, or xylene, chlorinated hydrocarbons such as chloroform or carbon tetrachloride or ethers such as diethyl ether, tetrahydrofuran, dioxane or the dialkyl ethers of ethylene glycol or the polyethylene glycols. Such solvents should be free of any groups which react with isocyanates, i.e. free of Zerewitinoff active hydrogen. Thus, solvents containing free hydroxy, thiol, carboxyl or like groups are not useful.

The reaction of the diols with the diisocyanates should also be maintained relatively free of water, not only because isocyanates react with water to form urea linkages but also because the carbon dioxide formed can cause foaming of the product.

Unlike the polyesters hereinafter described, the mixture of diols used to prepare the present polyurethanes should always be in the molar ratio desired in the final 7 product. Unlike polyester formation, where conditions are such that readjustment of the relative amounts of diols can take place, the usual conditions for polyurethane fonmation do not allow any such readjustment. The urethane linkage, once formed, remains intact.

(4) The examples: The following examples serve only to illustrate the acids and esters of this invention and their usefulness in greater detail, and are not to be considered as limiting the described invention in any manner.

The following examples 1-6 illustrate the preparation of the malonic acids and esters of this invention:

EXAMPLE 1 Sodium metal (9.7 g.) was added to 311 g. dry tertbutanol in an anhydrous system. After heating under reflux for 24 hours, reaction was not complete. 48 ml. dry methanol were added, causing the remaining sodium to react within one hour. Approximately 75 ml. of liquids were distilled from the mixture. The mixture was cooled to 50 C. and 69 g. of freshly distilled diethyl malonate were added dropwise over a six minute period. Then 250 ml. of liquid were distilled from the mixture under a nitrogen atmosphere, the mixture was cooled to 65 C. and 199 g. of F(CF CH CH I were added dropwise under a nitrogen atmosphere in ten minutes. The resulting mixture was heated under reflux for 2.5 hours during which time considerable white solids precipitated. Then about 250' ml. of liquid were distilled from the mixture at which point the pot temperature reached 120 C. The residue was cooled, ether was added and the solution was extracted with a few ml. of 5% hydrochloric acid. The aqueous layer was made more strongly acidic and extracted with ether. The combined ether solutions were washed with water and dried over anh. sodium sulfate. Distillation under reduced pressure gave 15.3 g. of impure starting material F(CF CH CH I, B.P. 74.590 C./23 mm., and 108.4 g. of mixed methyl and ethyl esters of F(CF CH CH CH(CO H) (3,3,4,4,5,5, 6,6,- 7,7,8,8,8 tridecafluorooctylmalonic acid)n 1.3619- 1.348l, 52.5% yield.

EXAMPLE 2 The mixture of methyl and ethyl esters of F(CF CH CH CH(CO H) 98.2 g.) obtained in Example 1 was added dropwise over a period of 11 minutes to an agitated solution of 6'6 g. of 85% potassium hydroxide in 70 ml. water at 6373 C. under a nitrogen atmosphere. The mixture was then heated under reflux for one hour, then the resulting alcohols were allowed to distill from the system. Water (50 ml.) was added at 19 C., then a mixture of 150 ml. concd. hydrochloric acid and 50 g. ice dropwise, resulting in a thick, cream-colored paste. A further 100 ml. water, then a small portion of ether were added, resulting in a two phase system. The mixture was extracted three times with ether and the combined ether extracts were dried over calcium sulfate. After the solids were removed by filtration and the ether was evaporated, the resulting yellowish solid was recrystallized from anisole. Three crops of crystals of F(CF CH CH CH(CO H) were obtained as follows.

(I) M.P. 108-109 C., 53.7 g., white, neutral equivalent 225.

Analysis.-Calcd. for C BA- 0 (percent): C, 29.32; H, 1.56; F, 54.90; (mol. weight, 450). Found (percent): C, 29.45; H, 1.60; F, 55.45. (M01. weight, 450.)

(I1) M.P. 98l00 C., 15.77 g. white, neutral equivalent 236, mole weight 472.

(III) M.P. 96-100 C., 2.7 g., white, neutral equivalent 238. (M01. weight 476.)

Overall yield of F(CF CH CH CH(C0 H) 72.1 g., 80.1%.

A yellowish residue from the above recrystallizations was distilled in a microstill, giving 2.8 g. of material,

B.P. 9498 C./0.6-0.8 mm., which solidified on cooling. Recrystallization from a mixed trichlorotrifluoroethane-petroleum ether solution at carbon ice temperature gave F(CF CH CH CH CG H, M.P. 5455 C.

Analysis.-Calcd. for C H F O (percent): C, 29.56; H, 1.72; F, 60.84. (M01. Weight 406.) Found (percent): C, 29.25; I-I, 1.70; F, 60.45. (Mol. weight 407.)

The acid possessed strong I.R. peaks at 3.2-3.8 and 5.83; (Nujol mull) or 3.03.57p. and 5.81 chloroform solution), indicating OH and carbonyl. The tridecafiuorodecanoic acid resulted from decarboxylation of the malonic acid.

EXAMPLE 3 Example 1 was repeated by reacting 23 g. sodium inetal with 604 g. purified tert-butanol. In this case, the mixture was heated intermittently until the sodium dissolved, without adding methanol as in Example 1. Then 168 g. of distilled diethyl malonate were added dropwise (one hour) at 3472 C. and the resulting mixture was heated at 70-75 C. for one-half hour. Then 474 g. of F (CF CH CH I were added at 7-0-75 C. (20 minutes) and the resulting mixture was heated under nitrogen for 20' hours at C. The mixture was then distilled at atmospheric pressure until the pot temperature reached 120 C., 740 ml. of distillate collected.

The residue was cooled to 21 C. and 200 ml. water were added. The mixture was extracted with ether and the combined ether extract dried over sodium sulfate. The ether was evaporated and the residue distilled under reduced pressure, giving 58.2 g. of starting materials, B.P. 44/10 mm. to 92/1.05 mm., 332.6 g. of primarily the diethyl ester (containing 5-9% tert-butyl ester groups) of F(CF CH CH CH(CO H) yield 74%, B.P. 95 C./l.0 mar-105 C./0.30 mm., 12;? 1.3602- 1.3567, and 79.2 g. of primarily diethyl ester of B.P. C./0.21 mm.128 C./0.30 mm., 11 1.3548- 1.3478, yield 15%.

EXAMPLE 4 Example 3 was repeated replacing the 474 g. of F(CFZ)GCHZCHZI g. Of After heating and isolating as in Example 3, a 75.5% yield of F(CF CH CH CH(CO C H was obtained, B.P. 107-108 -C./0.4 mm.

Analysis.-Calcd. for C H O F (percent): D, 33.7; H, 2.5; F, 53.3.Found (percent): C, 33.5; H, 2.4; F, 53.5.

EXAMPLE 5 Example 3 was repeated replacing the 474 g. of g. Of After heating and isolating as in example 3, a 77% yield Of F(CF2)1OCHZCH2CH(COZC2H5)Z was obtained, B.P. 122123 C./0.35 mm.

AnaZysis.-Calcd. for C H OgF (percent): C, 32.3; H, 2.1; F, 56.5. Found (percent): C, 32.3; H, 2.2; 'F, 56.5.

EXAMPLE 6 Example 3 was repeated replacing the 474 g. of F(CF CH CH I with 644 g. of

(tolylate ester of F(CF (CH OH). After heating and isolating as before, a yield of was obtained; B.P. 136-138 C./0.05 mm.

Analysis.-Calcd. for C H O F (percent): C, 45.6; H, 5.2; F, 39.1. Found (percent): C, 46.0; H, 5.4; F, 39.4. Employing the procedures described in Examples 1-6, any of the malonic esters and acids described in Section A herein can be prepared by replacing the reactants and bases with others listed therein.

The following Examples 7-11 illustrate the preparation of the 1,3-propanediol intermediates that can be prepared from the esters of this invention.

EXAMPLE 7 A solution of 51 g. of F(CF CH CH CH (CO C H in 200 ml. dry purified diethyl ether was added dropwise to a stirred slurry of 7.6 g. lithium aluminum hydride in 500 ml. dry purified ether under nitrogen. The addition took one hour, while maintaining the mass under gentle reflux. After addition was complete, the mass was heated under reflux for two hours. Ethyl acetate (30 ml.) was added dropwise to the cooled mixture followed by 400 g. of 10% aqueous sulfuric acid. After stirring for a short time, the resulting mixture was separated and the aqueous layer extracted with ether. The combined ether layers were dried over anh. sodium sulfate. Evaporation of the ether gave 33.1 g. of crude white crystals, M.P. 5565 C. and 6.1 g. of liquid. Distillation of the liquid under reduced pressure indicated it to be a mixture of starting ester and a substance which appeared to be F FzhCHzCH2CH-CH OH 020211, due to incomplete reduction The solids were recrystallized from an 80/20 (by volume) mixture of benzene/acetonitrile, giving 29.4 g. of

[2-(3,3,4',4',5,5,6',6',7',7,8',8',8-tridecafluoroctyl 1, 3-propanediol], M.P. 72.5-73.5 C. The product may also be recrystallized from chloroform.

Analysis.--Calcd. for C H F O (percent): C, 31.29; H, 2.61; F, 58.52; 0, 7.58. Found (percent): C, 31.2; H, 2.6; F, 58.5.

The nuclear magnetic resonance spectra in the H1 and F regions agreed with the assigned structure EXAMPLE 8 A solution of 85.2 g. of

in 200 ml. dry and purified diethyl ether was added dropwise to a stirred slurry of 9.5 g. lithium aluminum hydride in 500 ml. dry ether under nitrogen. The addition took 82 minutes, keeping the mass at gentle reflux. After addition, the mass was heated under reflux for 4 hours.

After cooling to 18 C., 500 g. of sulfuric acid were added dropwise to the stirred slurry. The resulting mixture was separated and the aqueous layer extracted with ether. The combined ether solutions were dried over sodium sulfate. Evaporation of the ether and recrystallization of the resulting crude product from chloroform gave the following:

Crop 1: 66.2 g. M.P. 77-77.5 C., white crystals, strong infrared peak at 3.01n.

Crop 2: 2.7 g., M.P. 62-65 C., oflF-white crystals, medium strong infrared peak 3.0l,u, and trace peak at 5.85;]. due to ester carbonyl.

Residue: Viscous amber liquid, infrared spectrum containing both hydroxyl and carbonyl peaks.

Analysis.(Crop 1), Calcd. for C H F O (percent): C, 29.7; H, 1.8; F, 64.3; 0, 4.2. Found (percent): C, 29.5; H, 1.8; F, 64.2.

Thus, Crop 1 was [F (CF CH CH C(CH OH) [2,2 bis(3',3',4,4',5',5,6,6,7,7',8',8,8' trideacfluorooctyl)-1,3-propanediol], yield (Crop 1 only) 86.2%.

EXAMPLE 9 Using the procedure of Example 7,

n-C F CH CH CH (CO C H 2 was caused to react with lithium aluminum hydride in a molar ratio of one mole ester to two moles hydride, giving n-C F CH CH CH(CH OH) in 78% yield, M.P.

- 10 Ill-114 C. Infrared analysis indicated freedom from ester groups.

Analysis.-Calcd. for C13H1102F17 (percent): C, 29.9; H, 2.1; F, 61.9. Found (percent): C, 29.9; H, 2.1, F, 5.93.

EXAMPLE 10 In the same manner as Example 7,

was caused to react with lithium aluminum hydride in a /2 mole ratio, giving n-C F CH CH CH(CH OH) in yield, M.P. l4ll43 C.

Analysis.--Calcd. for C H O F (percent): C, 28.9; H, 1.8; F, 64.1. Found (percent): C, 29.2; H, 1.8; F, 68.8.

EXAMPLE 11 In the same manner as Example 7,

was caused to react with lithium aluminum hydride in a /2 mole ratio, giving n-C F (CH CH(CH OH) in 81% yield, M.P. 90-91 C. after recrystallization from chloroform.

Analysis.Calcd. for C H O F (percent): C, 43.8; H, 5.3; F, 45.1. Found (percent): C, 44.2; H, 5.4; F, 43.6.

Using the above procedures of Examples 7-11, any malonic ester [RfR CH ,,(CO R) described in Section A herein may be reduced to the corresponding 1,3- glycol [R R'-] ,CH ,,(CH OH) The following Examples 12-33 illustrate the usefulness of the acids and esters of this invention and the diols prepared from them as condensation-polymer monomers.

EXAMPLE 12 A mixture of 5.1 g. F(CF22)GCH2CHQCH(OOZCZH5)2, 4.22 g. F(CF CH CH CH(CH OH) and 0.00284 g. tetraisopropyl titana-te was heated at 200 C. for 2.5 hrs. under nitrogen, allowing ethanol to distill as it forms from the melt. After 87% of the theoretical amount of ethanol had distilled, the system was placed under vacuum (0.3 mm.) and heated to 300 C. A substance began to distill so the system was cooled under nitrogen, when solidification occurred. 1

The resulting product melted completely by 55 C. The infrared spectrum showed a trace peak at 2.95 due to OH and a strong ester carbonyl peak at 5.73;.

Pieces of filter paper and cotton poplin were dipped into an ethyl acetate solution of the product, then allowed to air dry. Drops of Nujol purified petroleum oil on the surfaces of the paper and cloth samples did not penetrate, demonstrating that the product had rendered the paper and cloth oil repellent.

EXAMPLE 13 The polymer O CH2CHCH20zC-COH4C 0} 2) 2 C a F 13 had an inherent viscosity of 0.14 as a 0.5% solution in chloroform at 30 C.

Analysis.Calcd. for C H O F (percent): C, 40.2;

H, 2.4; F, 45.6. Found (percent): C, 41.2, 41.3; H, 2.4,

1 1 EXAMPLE 14 A mixture of 17.0 parts n-'C F CH CH CH(CH OH) 7.5 parts ethylene glycol, 15.5 parts dimethyl terephthalate (mole ratio 'C F 'CH CH CH (CHZOH)2/ ethylene glycol=0.35/ 1, mole ratio total diols/diester=2/ 1), 0.006 part antimony trioxide and 0.025 part calcium acetate monohydrate was placed in reaction vessel fitted for agitation, maintaining anhydrous conditions and a nitrogen atmosphere and application of vacuum. After purging for 30 minutes with nitrogen, the mass was heated at 185 C. for 3 hours, then at 200 C. for 3 hours. During this time, 69% of the expected methanol distilled from the mass. Additional heating for 2 hours at 220 C. gave an additional 23% of the methanol (total 92%). Heating was continued for 2.5 hours while the temperature was increased to 275 C. and the pressure reduced to 14 mm. 'Finally, the pressure was reduced to 0.05 mm. and heating was continued at 275280 C. for 2 hours, at which time no further apparent increase in viscosity was occurring. The polymer was then allowed to cool.

The polymer was found to consist of in the mole ratio 1/1 polymerized with terephthalic acid. Analysis.-Calcd. for C H O F (percent): C, 46.8; H, 2.8; F, 33.2. Found (percent): C, 46.9, 47.1; H, 3.0, 3.0; F, 33.2, 33.2.

The polymer had an inherent viscosity of 0.34 as a 0.5% solution in chloroform at 30 C. Inherent viscosity is determined according to the equation where C is the concentration of polymer in grams per 100 ml. of solution, N is the measured viscosity of the solution and N is the measured viscosity of the solvent.

EXAMPLE 15 Example 14 was repeated under similar conditions, giving a polymer of inherent viscosity 0.17 as a 0.5% solution in chloroform at 30 C.

A'naZysis.-Found (percent): C, 47.8, 47.7; H, 3.1, 3.1; F, 33.0, 33.1.

EXAMPLE 16 Example 14 was repeated under similar conditions giving a polymer of inherent viscosity 0.22 as a 0.5% solution in chloroform at 30 C.

Analysis.-Found (percent): C, 47.4, 47.6; H, 2.8, 2.8; F, 32.0.

EXAMPLE 17 Example 14 was repeated using 34.0 parts II-CGFHCHZCHZCH 2 5.0 parts ethylene glycol and 15.5 parts dimethyl terephthalate (mole ratio The heating was carried out as follows: 180-18l7 C. for 2.75 hours, 220-226 C. for 2.5 hours, collecting 80% of the expected methanol. Heating was continued for 2 hours at 245 C. while slowly reducing the pressure to 0.4 mm. Heating was continued at this pressure for 2 hours at 245-255" C., then 2.5 hours at 255285 C.

The resulting polymer had an inherent viscosity of 0.03 as an 0.18% solution in chloroform. The resulting polymer was found to contain C F CH CH CH(CH OH) and HOCH CH OH in the mole ratio of 7/ 3.

Analysis.Calc-d. for C H O F (percent): C, 43.2; H, 2.7; F, 39.6. Found (percent): C, 43.7; 43.6; H, 2.7, 2.5; F, 40.8

EXAMPLE 18 Example 14 was repeated using 20.9 parts U-C8F17CH2CHZCH 2 7.5 parts ethylene glycol (molar ratio=1/3), 15.5 parts dimethyl terephthalate, 0.006 part antimony trioxide and 0.025 part calcium acetate monohydrate. Heating was carried out as follows: 185 C., 4.5 hours, 210 C., 3.5 hours, collecting 71% of the expected methanol. The pressure was reduced slowly during 2 hours to 250 mm. while heating at 210 C. The temperature over the next min. was increased to 268 C. and the pressure was reduced to 0.04 mm. Heating was continued for 1.5 hours at 270 C. and 0.025 mm.

The resulting polymer contained the two glycols in a 1/1 molar ratio and had an inherent viscosity of 0.41 as a 0.5% solution in chloroform at 30 C.

Analysis.Calcd. for C H O F (percent): C, 44.2; H, 2.3; F, 38.4. Found (percent): C, 45.2, 45.1; H, 3.4, 3.5; F, 38.1, 38.1

EXAMPLE 19 Example 14 was repeated using 24.9 parts n-C F CH CH CH( CH OH) 2 7.5 parts ethylene glycol (molar ratio-=1/3), 15.5 parts dimethyl terephthalate, 0.006 part antimony trioxide and 0.0025 part calcium acetate monohydrate. Heating was carried out as follows: -185 C.-5 hours, 200 C.2 hours. About 79% of expected methanol was collected. During one hour the pressure was reduced to 75 mm. and the temperature increased to 265 C. The pressure was further reduced to 0.05 mm. and heating was continued for one hour at 265 C. and one hour at 275 C.

The resulting polymer contained the two glycols in the molar ratio of 1/ 1.

EXAMPLE 20 Example 14 was repeated using 11.0 parts fi l3 2 u z 2 3.7 parts ethylene glycol (molar ratio 1/ 3), 7.8 parts dimethyl terephthalate, 0.006 part antimony trioxide and 0.025 part calcium acetate monohydrate. Heating was carried out as follows: 160194 C.-6 hours, giving 84% of theoretical methanol, the temperature was increased to 258 C. and the pressure reduced to 1.0 mm. over one hour. Heating was continued at 258-270 C./1.0 mm. for one hour.

The resulting polymer contained the two glycols in a 1/1 molar ratio.

EXAMPLE 21 Example 14 was repeated using 30.7 parts ti 13 2 2]2 2 )2 7.5 parts ethylene glycol, 15.5 parts dimethyl terephthalate, 0.006 part antimony trioxide and 0.025 part calcium acetate monohydrate. Heating was carried out as follows: 3 hours185 C., 3 hours200204 C., 2.5 hours at 220250 0, giving 62% of expected methanol. The pressure was reduced to 0.1 mm. Hg during the next 3 hours while increasing the temperature to 283 C. Heating was continued at 283 C./0.1-0.2 mm. for 2 hours.

The product contained the two glycols in a 1/1 molar ratio and had an inherent viscosity of 0.24 as a 0.5% solution in chloroform at 30 C.

Analysis.Calcd. for C H ,O F (percent): C, 40.7; H, 2.2; F, 45.3. Found (percent): C, 42.2, 42.7; H, 2.6, 2.7; F, 44.8.

EXAMPLE 22 (A) A mixture of 17.0 parts of 7.5 parts ethylene glycol, 13.6 parts dimethyl terephthalate, 2.3 parts dimethyl sebacate, 0.006 part antimony trioxide and 0.025 part calcium acetate was heated as follows: 186205 C.4 hours giving 86% of expected methanol pressure reduced to 0.1 mn1.2.5 hours, temperature increased to 265 C., heated for 3 hours.

The resulting polymer contained the two glycols in the molar ratio 1/1 and the two acids in the molar ratio terephthalic/sebacic=7/ 1. It had an inherent viscosity of 0.23 as a 0.5 solution in chloroform at 30 C.

Analysis.-Calcd. for C H O F (percent): C, 47.0; H, 3.2; F, 32.8. Found (percent): C, 48.2, 48.0; H, 3.5, 3.5; F, 32.3.

(B) The procedure of part A was repeated using 17.0 parts n-C F CH CH CH(CH OH) 7.5 parts ethylene glycol, 11.6 parts dimethyl terephthalate and 4.6 parts dimethyl sebacate.

The resulting polymer contained the two glycols and the two acids in 1/ 1 molar ratios.

EXAMPLE 23 In a manner similar to the preceding examples, a copolymer of n-C F CH CH CH(CH OH) and dimethyl 4,4-bibenzoate was prepared.

EXAMPLE 24 Using the procedure of Example 14, a mixture of 34.0 part n-C F CH CH CH(CH OH) 5.0 parts ethylene glycol, 21.6 parts dimethyl 4,4'-bibenzoate, 0.006 part antimony trioxide and 0.025 part calcium acetate was heated as follows: 7 hours220 C., 86% methanol, pressure reduced to 0.7 mm., heated at 225 C./0.7-1.0 mm. for 4.5 hours.

The resulting polymer contained the glycols in the molar ratio It has an inherent viscosity of 0.13 as a 0.5% solution in chloroform at 30 C.

Analysis.-Calcd. for C H O F (percent): C, 51.4; H, 3.0; F, 33.2. Found (percent): C, 51.1, 51.3; H, 5.1, 5.6; F, 33.7.

EXAMPLE 26 Using the procedure of Example 14, a mixture of 20.9 parts n-C F CH CH CH(CH OH)2, 7.5 parts ethylene glycol, 21.6 parts dimethyl 4,4'-bibenzoate, 0.010 part antimony trioxide and 0.030 part calcium acetate monohydrate was heated as follows: 185 C.18 hours, 185- 200 C.5 hours, 235-245 C.-4 hours, 235 C./230 mm.l.5 hours, 270 C./0.1 mm.3 hours.

The resulting polymer contained the two glycols in an equimolar ratio.

EXAMPLE 27 Using the procedure of Example 14, a mixture of 30.8 parts [n C F CH CH C(CH OH) 2.48 parts ethylene glycol, 10.8 parts dimethyl 4,4'-bibenzoate, 0.010 part antimony trioxide and 0.030 part calcium acetate was heated as follows: 180-195 C.4 hours, 195-220 C.-- hours, 225-260 C./760-0.4 mm.2 hours, 260- 271 C./0.4 mm.-0.025 mm.--2.5 hours.

The resulting polymer contained the two glycols in an equimolar ratio.

EXAMPLE 2 8 Using the procedure of Example 14, a mixture of 17.0 parts n-C F CH CH CH(CH OH) 7.5 parts ethylene glycol, 15.5 parts dimethyl isophthalate, 0.006 part antimony trioxide and 0.025 part calcium acetate monohydrate was heated as follows: 180 C.3 hours, 220 C.-

14 A 4 hours, 220250 C.1 hour, 250 C./760-0.3 mm.- 3 hours, 250-288 C./0.2-0.03 mm.--1.5 hours.

The resultin polymer contained the two glycols in an equimolar ratio. It had an intrinsic viscosity of 0.32 as a 0.5% solution in chloroform at 30 C.

Analysis.-Calcd. for C H O F (percent): C, 46.8; H, 2.8; F, 33.2, Found (percent): C, 46 .7, 46.9; H, 2.8, 2.7; F, 33.3.

EXAMPLE 29 The procedure of Example 14 was repeated using 17.0 parts n-C F CH CH CH(CH OH) 7.5 parts ethylene glycol, 11.6 parts dimethyl isophthalate, 2.0 parts dimethyl maleate, 0.006 part antimony trioxide and 0.025 part calcium acetate monohydrate. Heating was carried out as follows: 205-210 C.-4.5 hours, 197-208 C./20 mm.-3 hours, 208209 C.0.20.3 mm.

The resulting polymer contained the two glycols in an equimolar ratio and the two acids in the molar ratio 3 isophthalate/ 1 maleate.

EXAMPLE 30 Using the procedure of Example 14 a mixture of 16.9 parts of n-C F CH CH CH(CH OH) and 7.5 parts of ethylene glycol, and 19.5 parts of dimethyl 1,4-naphthalenedicarboxylate, 0.006 part of antimony trioxide and 0.025 part of calcium acetate monohydrate was heated as follows: 17.5 hours at 185 C., 6 hours at 185-222 C., 2.5 hours at 222260 C./760-2 mm., and 7.5 hours at 230-268 C./0.50.7 mm. The resulting polymer contained the glycols in an equimolar ratio.

EXAMPLE 31 Using the procedure of Example 14 a mixture of 16.9 parts of n-C F CH CH CH(CH OH) and 14.2 parts of 1,6-hexanediol, and 15.5 parts of dimethyl terephthalate, and 0.006 part of antimony trioxide, and 0.025 part of calcium acetate monohydrate was heated as follows: 6 hours at 185-195 C., 11 hours at ZOO-226 C., 4 hours at 195 C./760-0.8 mm., 6.5 hours at 250-266 C./ 0.25-0.65 mm. The resulting polymer contained the glycols in an equimolar ratio.

EXAMPLE 32 To 17.0 parts n-C F CH CH CH(CH OH) at C. were added over a period of 20 minutes 5.28 parts of toluene diisocyanate consisting of 80% 2,4-isomer and 20% 2,6-isomer. Towards the end of the addition, the reaction mass became viscous so the temperature was increased to C., then held at 140-160 C. for 75 minutes. No further viscosity increase was observed after 3 hours at C. Filaments could be drawn from the melt,

Contact angles were determined as in Example 36 with the following results: water, advancing 115, receding 65; hexadecane, advancing 70, receding 63.

EXAMPLE 33 (A) Preparation of bischloroformate A solution of 21.1 parts n-C F CH CH CH(CH OH) in 11.9 parts acetone was added over a period of 75 minutes to six molar equivalents of liquid phosgene at 15 C. in a vessel cooled with a carbon-ice condenser and provided with an efiicient off-gas scrubber. The resulting mixture was held at 15 C. for one hour, then was allowed to warm to room temperature while purging with nitrogen to remove excess phosgene. After purging overnight, 24.5 parts (89.4%) of clear colorless liquid with an infrared spectrum consistent with the structure Analysis.-Calcd. for C H O Cl F (percent): C, 28.5; H, 1.6; F, 45.1. Found (percent): C, 29.9, 30.3; H, 1.8, 1.9;F, 45.2, 45.3.

(B) Preparation of polyurethane To 2.15 parts anhydrous piperazine heated to 110 C. was added under nitrogen during min. 13.7 parts of A further 0.5 part piperazine was added and heatin was continued for minutes. After cooling, the crude polymer was dissolved in chloroform, washed with water and then was precipitated by pouring into methanol. The polymer was shown to have the structure then was precipitated by pouring methanol. The polytion in chloroform at C.

Analysis,-Calcd. for C17H1704N2F13 (percent): C, 36.4; H, 3.0; F, 44.1. Found (percent): C, 35.2; H, 3.7; F, 44.8.

When applied to 80 x 80 cotton fabric at 5% OWF from chloroform, dried and cured for 3 min. at 180 C., the resulting cloth had a 50 Water repellency rating and a 3 oil repellency rating when tested by the test methods described in Example 34. Contact angles with Water and hexadecane, determined as described in Example 35, were as follows: water, advancing 115, receding 66; hexadecane, advancing 68, receding 60.

As seen in the foregoing example, the urethanes can also be prepared by condensing a bischloroformate with primary and secondary saturated aliphatic or aromatic diamines. The bischloroformates are prepared by reacting the chlorinated diol with phosgene, usually in an inert solvent. The condensation of the bischloroformate with the diamine is usually carried out by adding chloroformate at elevated temperatures. The aliphatic diamines may be diaminoalkanes such as ethylene diamine, 1,3-propylene diamine, 1,4-butylene diamine, 1,6-diaminohexane, 1,8- diaminooctane, 1,10-diaminodecane, 1,12-diaminododecane or 1,16-diaminohexadecane, diaminocycloalkanes such as 1,3-diaminocyclohexane, 1,4-diaminocyclohexane and the like or cyclic diamines such as piperazine and the like. The aromatic diamines include the phenylene diamines, the toluene diamines, the nitrophenylene diamines, diaminodiphenyl, diaminodiphenyl ether, 4,4'-diamino 3,3'-dichlorodiphenyl, 4,4-diamino-3,3'-dichlorodiphenyl ether, 4,4-diaminodiphenylmethane, 4,4'-diamino-3,3-dichlorodiphenylmethane, 4,4'-diaminodibenzyl, 4,4di amino-3,3'-dimethyldiphenyl, and the corresponding 2,2- dimethyl compound, 4,4-diamino-3,3-dimethoxydiphenyl, 4,4-diamin0-2,2'-dichloro 5,5 dimethoxydiphenyl, the various naphthalene diamines (1,2-, 1,3-, -l,4-, 1,5-, 1,6-, 1,7-, 1,8-, 2,3-, 2,7-), the various monochloro, monomethyl and mononitro derivatives of these naphthalene diamines.

By replacing the diol used in Example 32 with any of those described in Section C-3 herein, any of the polyurethanes described therein can be obtained. Thus, for example, any one of n-CgF CH CH Cl-flCH OHh, IIC10F21CH2CH2CH2,

or n-C F (CH CH(CH OH) may be used without essential change. Also, in place of the mixed isocyanate used, any one of toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, methylene bis-(4-phenylisocyanate), 4,4-diisocyanatodiphenyl or 4,4'-diisocyanatodiphenyl ether may be used.

By employing the proper reactants described in Section Cl herein, any of the polymers disclosed in said Section C-l can be prepared according to the procedures described in Examples 12-31 and especially Example 14.

By employing the proper reactants described in Section C-2 herein, any of the polymers described therein can be prepared by replacing the diol reactant of Example 12 with any of the diols described in Section C2.

EXAMPLE 34 Solutions in chloroform of representative polymers prepared in the previous examples were applied to fabrics. After evaporation of the solvent, the fabrics were cured at C. for three minutes. The fabrics were then evaluated for oil and water repellency. Water repellency was determined using test method 22-1952 of the American Association of Textile Chemists and Colourists '(AST'M Method-D583-63). Oil repellency was determined using test method 118-1966T of the American Association of Textile Chemists and Colourists. Both tests are described in the Technical Manual, 1966, of the aforenamed Association. The results are shown below in the table.

It has recently been shown by Johnson and Dettre [Advances in Chemistry Series No. 43, 112l35 (1964), J. Phys. Chem, 68, 1744 (1964), ibid., 69, 1507 (1965)] that the usefulness of textile treating agents as oil and water repellent agents may be evaluated by measurements of contact angles of water and hexadecane on flat films of the polymers provided both advancing and receding contact angles are measured. In the capillary type system which exists in treated textiles, it is the advancing angles Which controls spreading and wicking [Furmidge, J. Colloid. Sci., 17, 309 (1962), Berch et al., Textile Research Journal, 35, 252-260 (1965)]. Thus both oil and Water repellency ratings are directly related to the advancing angles. The receding angles help predict whether or not droplets will release or be fully blotted off. The difference between the two angles is called contact angle hysteresis which is ideally as small as possible.

Measurements were carried out on representative polymers described hereinbefore with the results shown below. The sessile drop method described by Johnson and Dettre (loc. sit.) was used.

Examples 34 and 35, along with portions of Examples 12, 32 and 33, demonstrate the usefulness of the polymers. Most are oiland/ or water-repellent ingredients when applied to fabrics. In addition, some of the polymers can be drawn into fibers or filaments or can be cast from solution into self-supporting films.

The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations are to be understood therefrom. The invention is not limited to the exact details shown and described, for obvious modifications will occur to those skilled in the art.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A compound represented by the structura formula wherein R; is perfiuoroalkyl of 4-20 carbon atoms, R is alkylene of 2-12 carbon atoms, R is hydrogen or lower alkyl, and a is the whole number 1 or 2.

2. A compound of claim 1 wherein R is hydrogen.

3. A compound of claim 2 wherein R is perfluoroalkyl of 6-12 carbon atoms.

4. A compound of claim 3 wherein R is alkylene of 2-4 carbon atoms.

5. A compound of claim 4 wherein a is 1.

6. The compound of claim 5 having the structural formula F (CF CH CH CH( COOH) 7. A compound of claim 1 wherein R is lower alkyl.

8. A compound of claim 7 wherein R is perfluoroalkyl of 6-12 carbon atoms.

9. A compound of claim 8 wherein R is alkylene of 2-4 carbon atoms.

10. A compound of claim 9 wherein a is 1.

11. A compound of claim 10 having the structural formula 1 (CF CH CH CH(COOCH References Cited 'McBee et al.: JACS, 79, 2323-2325 (1957).

LORRAINE A. WEINBERGER, Primary Examiner E. J. SKELLY, Assistant Examiner U.S. Cl. X.R. 2605 

